So as expected, my log is included 2018.09.17 index but now it is included in 2018.09.16 index.
And 2018-09-17 09:01:01.111 time log included 2018.09.17 index normally.
I think it has something to do with timezone setting ( my server in korea UTD + 9 hour ) but i can't figure out what should i do.